Condensed Consolidated Statements of Cash Flows (Unaudited) - GAS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Activities:
Net income	$ 1,071	$ 799
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	1,261	1,233
Other, net	76	51
Changes in certain current assets and liabilities —
Receivables	52	790
Natural gas for sale, net of temporary LIFO liquidation	237	267
Natural gas cost under recovery	0	108
Other current assets	(27)	34
Accounts payable	(423)	(1,056)
Accrued compensation	(488)	(478)
Other current liabilities	103	75
Net cash provided from operating activities	1,311	844
Investing Activities:
Property additions	(1,770)	(1,850)
Cost of removal, net of salvage	(138)	(135)
Change in construction payables, net	(365)	(140)
Other investing activities	(111)	(91)
Net cash used for investing activities	(2,385)	(2,118)
Financing Activities:
Short-term borrowings	(550)	(400)
Payment of common stock dividends	(733)	(742)
Other financing activities	(124)	(83)
Net cash provided from financing activities	985	454
Net Change in Cash, Cash Equivalents, and Restricted Cash	(89)	(820)
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	921	2,037
Cash, Cash Equivalents, and Restricted Cash at End of Period	832	1,217
Supplemental Cash Flow Information:
Interest, net of amounts capitalized	714	652
Income taxes, net	(9)	(9)
Noncash transactions —
Accrued property additions at end of period	580	833
Right-of-use assets obtained under operating leases	14	26
SOUTHERN Co GAS
Operating Activities:
Net income	409	309
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	155	141
Deferred income taxes	61	27
Other, net	(10)	(3)
Changes in certain current assets and liabilities —
Receivables	(16)	266
Natural gas for sale, net of temporary LIFO liquidation	237	267
Prepaid income taxes	53	33
Natural gas cost under recovery	0	108
Other current assets	(27)	(18)
Accounts payable	(127)	(303)
Accrued taxes	7	36
Accrued compensation	(55)	(36)
Natural gas cost over recovery	(65)	117
Other current liabilities	(24)	34
Net cash provided from operating activities	598	978
Investing Activities:
Property additions	(255)	(299)
Cost of removal, net of salvage	(12)	(24)
Change in construction payables, net	(40)	(53)
Other investing activities	(12)	(3)
Net cash used for investing activities	(319)	(379)
Financing Activities:
Decrease in notes payable, net	(81)	(448)
Short-term borrowings	0	(200)
Capital contributions from parent company	0	192
Payment of common stock dividends	(151)	(146)
Other financing activities	(3)	9
Net cash provided from financing activities	(235)	(593)
Net Change in Cash, Cash Equivalents, and Restricted Cash	44	6
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	35	83
Cash, Cash Equivalents, and Restricted Cash at End of Period	79	89
Supplemental Cash Flow Information:
Interest, net of amounts capitalized	89	76
Income taxes, net	(3)	0
Noncash transactions —
Accrued property additions at end of period	99	124
Right-of-use assets obtained under operating leases	$ 1	$ 0